Mold core for monolithic concrete walls



P. B. WALKER, JR.

MOLD CORE FOR MONOLITHIC CONCRETE WALLS.

APPLICATION FILED SEPT. 71 1920.

1,403, 23, Patented Jan. 17,1922.

2 SHEETS-SHEET 1.

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326011225 .wa/lk r P. B. WALKER, JR. MOLD CORE FOR mowommc CONCRETE WALLS. APPLICATION FILED SEPT, 7, 1920. 1 403 8 23 Patented Jan. 17, 1922.

2 SHEETSSHEET 2- .view of one of the lateral air UNITED STATES PLATT B. WALKER, JR., OF ST. PAUL, MINNESOTA.

MOLD COR-E FOR MONOLITHIC CONCRETE WALLS.

Specification of Letters Patent.

Patented Jan. 17, 1922.

Application filed September 7, 1920. Serial No. 408,581.

To all whom it may concern Be it known that I, PLATT B. lVALnnn, J12, a citizen of the United States, residing at St. Paul, in the county of Ramsey and State of Minnesota, have invented a new and useful Mold Core for Monolithic Concrete ails, of which the following is a specification.

This invention has for its object to provide an improved core mold for concrete walls wherein a continuous air space is produced. More particularly the construction of concrete wall provided by my invention has vertical sides spaced laterally and connected by integral vertical webs extending from top" to bottom to form vertical cells or air spaces, said webs being perforated at intervals to connect said cells. My improved core mold is so constructed that a plurality thereof can be easily and quickly assembled between the usual outside walls of a mold and after the concrete is poured and allowed to set, contracted and withdrawn from the finishedwall, said operation being easily and quickly accomplished and facilitating the building of concrete walls in an ellicien-t and inexpensive manner.

In the accompanying drawings forming partof this specification, Fig. 1 is a perspective View of a detail of a concrete wall constructed in accordance with my invention, part thereof showing the completed wall and the remainder showing my improved core molds in place before withdrawal; Fig. 2 is a perspective view of one of my improved mold cores used for constructing a corner portion of two walls; Fig. 3 is a perspective passageway mold cores and spacer elements employed with'my invention for forming the connections' between the air cells; Fig. 4 is a plan of one of thespacer lock members; Fig. 5' is asection taken 011 the line 5-5 of Fig; 43; Fig. 6 is a plan of my improved mold core in normal or expanded condition; Fig. 7 is another plan of the mold core in contracted condition and Fig. 8 is a perspective view of the wall mold core in normal condition showing the openings for the spacer cores arranged for constructing a straight run of the wall.

In the drawings, F ig. 1 shows a monolithic wall A of concrete built up by the use of my improved mold core which ismade in two designs, the one shown in Fig. 8 for a straight'run and the other shown in Fig. 2' for corners. These two constructions are gether, in which position they substantially alike excepting that the lateral openings 10 for the s acing cores are arran ed in a slightly di erent position as will be hereinafter described. The wall has two vertical side portions 11 and 12 and vertical webs 13 spaced vertically apart, forming vertical air cells let which are connected by horizontal or lateral ducts 15, but it will, of course be understood that the wall may have more than two vertical side portions and hence more than one set of vertical air cells and lateral connecting ducts. The cross webs 13 widen at their junctions with the side portions 11 and 12 to increase the strength of the wall and reduce the tendency toward forming cracks between the webs and side portions.

My improved mold core A is made so that it can be caused to contract in size to facili tate withdrawal vertically after the concrete has been poured and allowed to set. This core consists of a pair of upright flexible or resilient plates 16 and 17 of similar shape, each plate being bent horizontally between its ends and the vertical ends of both plates being placed nearly together and being hingedly connected by short flat links 18 and 19. In normal position the ends of the plates and links produce the flat sides of the core, said sides being connected by curved ends 20 and 21. The links 18 and 19 are provided with vertical lever members 22 and 23 which when the sides of the plates 16 and 17 assume normal position fold inwardly toare separately locked together by a bail 2 1-. This nail is hinged by a pair of eyelets 25 on the lever member 23 and engages member 22 by shoulder pieces 26, which enter the openings 27, in member 22, in looking position. In this position the bail is releasably held by a button piece 28. The mold sections tend to spring outwardly and expand in which position theyv are locked. When the parts are contracted the links swing onto dead center thus automatically holding the mold sections against expanding until the lever members are swung inwardly together. The lever members extend across the space between the sides of the plates in normal position thus forming braces to prevent the sides from collapsing.

In use a plurality of mold cores are placed in spaced relation end to end in a horizontal series inwardly from the usual side members 30 and 31, to produce the vertical air cells 14 in the finished wall. After molding one section of the wall containing one horizontal series of mold cores, the cores are withdrawn and raised into position to mold with the same series, at a higher elevation, this procedure being repeated until the entire wall is completed. The ends 20 and 21 are formed with spacer core receiving openings 10, said spacer core B'consisting 01 a shell like structure formed out of a sheet of metal or other suitable material bent into a structure having top and bottom 32 and 33 and sides 3% and 35, all converging in a single direction and terminating in a curved nose end 36. This spacer core is insertable through the adjacent openings 10 of any ad j acent pair oi mold cores, the openings being so regulated in size that the spacer core will fit them tightly. In this condition the spacer core is locked tightly in place by means of a key 37, which is inserted downwardly through the hollow nose 36 back of the wall of the mold core. A shoulder 38 will limit the downward thrust of the key and a chamfered edge 39 on the key is arranged so that when the key is turned in one direction it will press against the inner sur face of the nose 36 and draw the spacer core tightly into the mold core and hold the latter in position. The corner mold cores are similar in construction to the mold cores for a straight runexcepting that the adjacent openings 10 of a pair of mold cores at the corner are arranged so as to receive the lateral spacer core at the desired angle.

Having described my invention what I claim as new and desire to secure by Letters Patent is:

1. In combination with a pair of spaced outside mold walls, a plurality of mold cores adapted to be positioned between said walls to produce a pair of contiguous air cells each of said cores consisting of a pair of substantially upright flexible plates, each plate being bent horizontally between its ends and the vertical ends of both plates being hingedly linked together, whereby in normal position the ends of the plates produce the sides of an air cell and when the links are turned inwardly said plates are contracted to permit free vertical with-.

drawal of the core from within the molded concrete wall, and a lateral spacing core, the

median portions of'the contiguous plates of said mold cores being perforated to removably and laterally receive said spacing core,

whereby air ductsareadapted to be formed in the walls connecting said cells.

2. In combination with a pair of spaced outside mold walls, a plurality of mold cores adapted to be positioned between said walls to produce a pair of contiguous air cells, each of said cores consisting of a pair of upright flexible plates, each plate being bent longitudinallybetween its ends and the vertical ends of both plates being movably linked together, whereby in normal posi tion the ends of the plates produce the sides of an air cell and when the links are turned inwardly said plates are contracted to permit free vertical withdrawal of the core from within the molded concrete wall, and a lateral spacing core, the median portions of the contiguous platesof said mold cores being perforated to laterally receive said spacing core, whereby air ducts are adpated to be formed in the walls connecting said cells, and said spacing core being re-movably keyed into the mold cores.

3. In combination with a pair of spaced outside mold walls, a plurality of mold cores adapted to be positioned between said walls to produce a pair of contiguous air cells, each of said cores consisting of a pair of upright flexible plates each plate being F bent horizontally between its ends and the vertical ends of both plates being arranged contiguous each other, hinge links connecting the vertical ends of both plates together, whereby in normal position the end portions 9 of the plates produce the sides of an air cell and when the links are turned inwardly said plates are contracted topermit free vertical withdrawal of the core from within the molded concrete wall, means for locking said links in out turned position to hold the sides of the core in normal position and a lateral spacing core, the median portions of the contiguous plates of said mold cores being perforated to removably and laterally'lQo receive said spacing cores, whereby air ducts are adapted to be formed in the walls connecting said cells. j v

45-111 combination with a pair of spaced" outside mold walls, a plurality of mold cores 1 adapted to produce a pair of contiguous air cells, each of said cores consisting of'a pair ofupright flexible plates, each plate being bent horizontally between its ends and the vertical ends of both plates being arranged 11o contiguous each other, hinge links connecting theends of both plates together, whereby in normal position the end portions of the plates produce the sides of an air celland when the links are turned inwardly said plates are contracted to permit free with-- drawal of the core from within the molded concrete wall, a spacing core having converging sides, the median portions of the contiguous plates of said mold cores being 12 perforated to receive the converging sides of said spacin core under wedging action and means for oldingthe spacing core tightly inserted through said perforations. r

5. In-combination with a pair of spaced outside mold walls, a plurality of mold cores adapted to be positioned between said walls. to produce a pair of contiguous air cells,

each of said cores consisting of apair of upright flexible plates each plate being bent horizontally between its ends and the vertical ends of both plates being arranged contiguous each other, hinge links connecting the ends of both plates together, whereby in normal position the end portions of the plates produce the sides of an air cell and when the links are turned inwardly said plates are contracted to permit'tree withdrawal of the core from within the molded concrete wall, a lateral spacing core, the median portions of the contiguous plates of said mold cores being perforated to removably and laterally receive said spacing core, whereby air ducts are adapted to be formed in the walls connecting said cells and means for locking said spacing core in said mold cores.

6. A contractible mold core, comprising, in combination, a pair of flexible plates bent between their ends to form pairs of sides, said sides when in vertical position being placed end to end, links hinged between the adjacent ends of said plates adapted in nor mal position to spread the plates and when turned to contract said plates, and means for holding said links in normal position.

7. A contractible mold core, comprising,

in combination, a pair of flexible plates bent between their ends to form pairs of sides, the sides of each pair tending to expand, said sides when in vertical position being placed end to end, links hinged between the adjacent ends of said plates adapted normally to permit the plates to expand and when turned into a position approachin dead center to hold the plates contracted, lever members secured to said linksby which the links can be turned inwardly and adapted to abut when the links and ends of the core plates assume normal position and means for locking the lever members in abutting position.

8. A contractible mold core, comprising, in combination, a pair of resilient plates bent between their ends to form pairs of sides and curved ends, said sides when in vertical position being placed end to end and tending to spread apart and expand the ends and link members hinged between the adjacent vertical ends of the sides.

In testimony whereof, I have signed my name to this specification.

PLATT B. VALKER, J R. 

